I just started flying a
Mavic Air 1 myself (having owned a
Phantom 4 Pro v1 for a few years I am not new to drones) and I ultimately ended up using an old cellphone as a dedicated device. It is an LG V20, primarily chosen for the replaceable battery, but it has a defective main microphone which makes it useless as a phone (have to hold it exactly the right way and distance for people to hear you), so I factory reset it and set it up for DJI Go 4 for the
MA1.
The display is almost the same size as my Galaxy S9+ phone, it has a ton of battery life for drone use (I charge it only after I am done flying the
MA1 through about 5 batteries and still have about 60-70%+ battery life and that is with GPS/WiFi running and brightness maxed out). I also put a matte screen protector on to help with glare. I say help, because if you have the sun directly reflecting you still get a bright spot, just not a 100% intense direct reflection. I use polarized sunglasses all the time and find it about 80-90% effective in cutting even non-direct glare out, which is more than enough to enjoy flying the
MA1. The screen is big enough to not miss information that pops up, I also have no difficulty selecting options and bringing up menus and such on the fly. Anything smaller would just suck in my opinion. Recharging is easy as I just use the DJI
MA1 cable without the micro-usb adapter since the LG V20 is a USB-C connection. I do run it in Airplane mode with WiFi auto-connect turned off to keep disruptions of the DJI Go 4 experience to nothing. If I find I need connectivity out and about I can always put a sim-card in the phone and have data access via my cell plan, but downloading maps works just fine over WiFi for now. Especially being someplace that has WiFi that I can access before a flight it is seamless. I even did a hotspot off my GS9+ once and just used that while I was flying without needing to deal with a sim-card. Again pretty easy to do and no risk of interference if you just choose the proper frequencies for the aircraft and then choose the other band for the hotspot.
I will say the LG V20 worked out excellent though, as it fits in the elastic pocket on the back of the
MA1 drone-only zippered case. I have a Ultimaxx waterproof case that holds my
DJI Goggles, the
MA1, the controller with modified 4Hawks Raptor SR antenna along with 5 batteries, charger, charging hub and the rest of the wires needed for the
MA1. I modified the case to fit the original
MA1 zippered drone case because I just was not comfortable with how the
MA1 bounced around in the case by itself. In doing that I was able to store the 4Hawks panel under the
MA1 case.
As a side-note, for my
P4P I use a Galaxy Tab Pro 8.4 with a custom rom and it runs great on that tablet, especially being an 8" display. I ordered a matte screen protector for that as well after using one on the LGv20 with the
MA1.